Benzothiazolones, and their production and use

ABSTRACT

A compound of the formula: ##STR1## wherein R is a C 1  -C 5  alkyl group, a C 3  -C 4  alkenyl group, a C 3  -C 4  alkynyl group, a C 1  -C 2  alkoxy(C 1  -C 2 )alkyl group, a C 1  -C 2  alkylthio(C 1  -C 2 )alkyl group or a mono- or polyfluoro(C 1  -C 3 )alkyl group, X is a C 1  -C 4  alkylene group which may be substituted with at least one methyl or a --OCH 2  -- group and n is an integer of 0, 1 or 2, which is useful as a herbicide.

This application is a divisional of copending application Ser. No.07/131,742 filed on Dec. 11, 1987.

The present invention relates to benzothiazolones, and their productionand use. More particularly, the invention relates to novelbenzothiazolones, a process for producing them, and their use asherbicides.

Certain benzothiazolone derivatives such as4-chloro2,3-dihydro-2-oxobenzothiazol-3-ylacetic acid (benazolin)[Herbicide Handbook of the Weed Science Society of America, 5th Ed., p.40 (1983)] are known to be effective as herbicides. However, theirherbicidal activity is not necessarily satisfactory.

It has now been found that the benzothiazolones of the formula: ##STR2##wherein R is a C₁ -C₅ alkyl group, a C₃ -C₄ alkenyl group, a C₃ -C4alkynyl group, a C₁ -C₂ alkoxy(C₁ -C₂)alkyl group, a C₁ -C₂ alkylthio(C₁-C₂)alkyl group or a mono- or polyfluoro(C₁ -C₃)alkyl group, X is a C₁-C₄ alkylene group which may be substituted with at least one methyl ora --OCH₂ -- group and n is an integer of 0, 1 or 2 show a highherbicidal activity against a wide variety of weeds includingbroad-leaved weeds, Graminaceous weeds and Commelinaceous weeds inagricultural plowed fields by foliar or soil treatments withoutproducing any material phytotoxicity on various agricultural crops suchas corn, wheat, rice plant, soybean, cotton and sugarbeet. Examples ofthe broad-leaved weeds include wild buckwheat (Polyqonum convolvulus),pale smartweed (Polygonum lapathifolium), common purslane (Portulacaoleracea), common chickweed (Stellaria media), common lambsquarters(Chenopodium album), redroot pigweed (Amaranthus retroflexus), radish(Raphanus sativus), wild mustard (Sinapis arvensis), shepherdspurse(Capsella bursa-pastoris), hemp sesbania (Sesbania exaltata), sicklepod(Cassia obtusifolia), velvetleaf (Abutilon theophrasti), prickly sida(Sida spinosa), field pansy (Viola arvensis), catchweed bedstraw (Galiumaparine), ivy-leaf morningglory (Ipomoea hederacea), tall morningglory(Ipomoea purpurea), field bindweed (Convolvulus arvensis), jimsonweed(Datura stramonium), black nightshade (Solanum nigrum), persianspeedwell (Veronica persica), common cocklebur (Xanthium pensylvanicum),common sunflower (Helianthus annuus), scentless chamomile (Matricariaperforata), corn marigold (Chrysanthemum segetum), etc. Examples ofGraminaceous weeds include Japanese millet (Echinochloa frumentacea),barnyardgrass (Echinochloa crus-galli), green foxtail (Setaria viridis),large crabgrass (Digitaria sanguinalis), annual bluegrass (Poa annua),blackgrass (Alopecurus myosuroides), oats (Avena sativa), wild oats(Avena fatua), johnsongrass (Sorghum halepense), etc. Examples of theCommelinaceous weeds include asiatic dayflower (Commelina communis),etc.

The benzothiazolones (I) of the invention are also effective inexterminating paddy field weeds including Graminaceous weeds such asbarnyardgrass (Echinochloa oryzicola), broad-leaved weeds such as commonfalsepimpernel (Lindernia procumbens), indian toothcup (Rotala indica)and waterwort (Elatine triandra), Cyperaceous weeds such as hardstembulrush (Scirpur juncoides), needle spikerush (Eleocharis acicularis)and and water nutgrass (Cyperus serotinus), and others such asmonochoria (Monochoria vaginalis) and arrowhead (Sagittaria pygmaea)without producing any phytotoxicity to rice plants on floodingtreatment.

Among the benzothiazolones (I), preferred are those wherein R is a C₂-C₄ alkyl group, a C₃ -C₄ alkenyl group, a C₃ -C₄ alkynyl group or a C₁-C₂ alkoxymethyl group, X is a C₁ -C₂ alkylene group or a --OCH₂ --group and n is 0. More preferred are those wherein X is a C₁ -C₂alkylene group. Still more preferred are those wherein R is a C₂ -C₄alkyl group, a C₃ -C₄ alkenyl group or a C₃ -C₄ alkynyl group, X is a C₁-C₂ alkylene group and n is 0. The most preferred are those wherein X isa C₂ alkylene group. Typical examples of the preferred compounds are2-[6-fluoro-3(1-methylethyl)-2(3H)-benzothiazolon-5-yl]-4,5,6,7-tetrahydro-2H-benzotriazole-1-oxide,2-[6-fluoro-3-(2-propenyl)2(3H)-benzothiazolon-5-yl]-4,5,6,7-tetrahydro-2H-benzotriazole-1-oxide,2-[6-fluoro-3-(2-propynyl)-2(3H)-benzothiazolon-5-yl]-4,5,6,7-tetrahydro-2H-benzotriazole-1-oxide,etc.

The benzothiazolones (I) of the present invention are prepared byreacting a compound of the formula: ##STR3## wherein X and n are each asdefined above with a compound of the formula:

    R--Y                                                       (III)

wherein R is as defined above and Y is an acid-forming reactive groupsuch as a chlorine atom, a bromine atom, an iodine atom, amethanesulfonyl group or a p-toluenesulfonyl group, usually in a solventat a temperature of about 0° to 120° C. for a period of about 0.5 to 24hours in the presence of a base.

The compound (III) and the base may be respectively used in amounts ofabout 1.0 to 1.5 equivalents and of about 1.0 to 1.5 equivalents to thecompound (II). As the solvent, there may be used aromatic hydrocarbons(e.g. benzene, toluene, xylene), ethers (e.g. dioxane, tetrahydrofuran,diethyleneglycol dimethyl ether), nitriles (e.g. acetonitrile,isobutylonitrile), acid amides (e.g. formamide, N,N-dimethylformamide,acetamide), sulfur compounds (e.g. dimethylsulfoxide, sulphorane),water, etc. These may be used solely or in combination. Examples of thebase are inorganic bases (e.g. sodium hydroxide, potassium hydroxide,sodium carbonate, potassium carbonate, sodium hydride), etc.

After completion of the reaction, the reaction mixture is subjected toan ordinary post-treatment such as extraction with an organic solventand concentration. If desired, any conventional purification proceduresuch as chromatography or recrystallization may be adopted.

Alternatively, the benzothiazolones (I) of the invention are obtainableby reacting a compound of the formula: ##STR4## wherein R is as definedabove with a compound of the formula: ##STR5## wherein X and n are eachas defined above and R¹ and R² are, the same or different, each a C₁ -C₆alkyl group or, when taken together with the adjacent nitrogen atom,they represent a 5 to 7-membered nitrogen-containing heterocyclic ringoptionally containing an oxygen atom, followed by oxidative ringclosure.

The reaction between the compound (IV) and the compound (V) is normallyaccomplished in the presence of a small amount of an acid (e.g. aceticacid, p-toluenesulfonic acid) in a solvent such as alcohols (e.g.methanol, ethanol, cellosolve) or ethers (e.g. dioxane,tetrahydrofuran). In the reaction, the compound (V) may be used in 1 to1.05 equivalents to the compound (IV). The oxidative ring closure iscarried out in the existence of an oxidizing agent (e.g. cupric sulfate,platinum oxide, zinc tetraacetate) in a tertiary amine (e.g. pyridine,picoline) and a solvent such as water, alcohols (e.g. methanol, ethanol)or ethers (e.g. diethyl ether, diisopropyl ether, diethylene glycoldimethyl ether, dioxane, tetrahydrofuran) at a temperture of 10° to 100°C. for a period of 1 to 10 hours. The amount of the oxidizing agent andthe tertiary amine are respectively from 1.0 to 1.5 equivalents and from1 equivalent to a large excess to the compound (IV).

After completion of the reaction, the reaction mixture may be subjectedto a post-treatment by a per se conventional procedure, for instance,dilution with water, extraction with an organic solvent andconcentration. If necessary, any purification procedure such aschromatography or recrystallization may be adopted.

Typical examples of the benzothiazolones (I) which can be produced byany of the above procedures are shown in Table 1.

                  TABLE 1                                                         ______________________________________                                         ##STR6##                      (I)                                            R               X               n                                             ______________________________________                                        CH.sub.3        CH.sub.2        0                                             C.sub.2 H.sub.5 CH.sub.2        0                                             n-C.sub.3 H.sub.7                                                                             CH.sub.2        0                                             i-C.sub.3 H.sub.7                                                                             CH.sub.2        0                                             n-C.sub.4 H.sub.9                                                                             CH.sub.2        0                                             i-C.sub.4 H.sub.9                                                                             CH.sub.2        0                                             sec-C.sub.4 H.sub.9                                                                           CH.sub.2        0                                             CH.sub.3        CH(CH.sub.3)    0                                             C.sub.2 H.sub.5 CH(CH.sub.3)    0                                             n-C.sub.3 H.sub.7                                                                             CH(CH.sub.3)    0                                             i-C.sub.3 H.sub.7                                                                             CH(CH.sub.3)    0                                             sec-C.sub. 4 H.sub.9                                                                          CH(CH.sub.3)    0                                             i-C.sub.4 H.sub.9                                                                             CH(CH.sub.3)    0                                             i-C.sub.3 H.sub.7                                                                             C(CH.sub.3).sub.2                                                                             0                                             i-C.sub.3 H.sub.7                                                                             CH.sub.2        1                                             i-C.sub.3 H.sub.7                                                                             CH(CH.sub.3)    1                                             i-C.sub.3 H.sub.7                                                                             CH(CH.sub.3)    2                                             i-C.sub.3 H.sub.7                                                                             C(CH.sub.3).sub.2                                                                             1                                             CH.sub.2 CHCH.sub.2                                                                           CH.sub.2        0                                             CH.sub.2 CHCH.sub.2                                                                           CH(CH.sub.3)    0                                             CH.sub.2 CHCH.sub.2                                                                           C(CH.sub.3).sub.2                                                                             0                                              ##STR7##       CH.sub.2        0                                              ##STR8##       CH(CH.sub.3)    0                                              ##STR9##       C(CH.sub.3).sub.2                                                                             0                                              ##STR10##      CH.sub.2        1                                              ##STR11##      CH(CH.sub.3)    1                                              ##STR12##      C(CH.sub.3).sub.2                                                                             1                                              ##STR13##      CH.sub.2        0                                              ##STR14##      CH(CH.sub.3)    0                                              ##STR15##      C(CH.sub.3).sub.2                                                                             0                                              ##STR16##      CH.sub.2        0                                              ##STR17##      CH(CH.sub.3)    0                                              ##STR18##      C(CH.sub.3).sub.2                                                                             0                                             CHCHC(CH.sub.3).sub.2                                                                         CH.sub.2        0                                              ##STR19##      CH.sub.2        0                                             CH.sub.2 CCH    CH.sub.2        0                                             CH.sub.2 CCH    CH(CH.sub.3)    0                                             CH.sub.2 CCH    C(CH.sub.3).sub.2                                                                             0                                             CH.sub.2 CCH    CH.sub.2        1                                             CH.sub.2 CCH    CH(CH.sub.3)    1                                             CH.sub.2 CCH    C(CH.sub.3).sub.2                                                                             1                                             CH.sub.2 CCH    CH.sub.2        2                                             CH.sub.2 CCH    CH(CH.sub.3)    2                                              ##STR20##      CH.sub.2        0                                              ##STR21##      CH(CH.sub.3)    0                                              ##STR22##      C(CH.sub.3).sub.2                                                                             0                                              ##STR23##      CH.sub.2        1                                              ##STR24##      CH(CH.sub.3)    1                                             CH.sub.2 CCCH.sub.3                                                                           CH.sub.2        0                                             CH.sub.2 CCCH.sub.3                                                                           CH(CH.sub.3)    0                                             CH.sub.2 CCCH.sub.3                                                                           C(CH.sub.3).sub.2                                                                             0                                             CH.sub.3        (CH.sub.2).sub.2                                                                              0                                             C.sub.2 H.sub.5 (CH.sub.2).sub.2                                                                              0                                             n-C.sub.3 H.sub.7                                                                             (CH.sub.2).sub.2                                                                              0                                             i-C.sub.3 H.sub.7                                                                             (CH.sub.2).sub.2                                                                              0                                             n-C.sub.4 H.sub.9                                                                             (CH.sub.2).sub.2                                                                              0                                             i-C.sub.4 H.sub.9                                                                             (CH.sub.2).sub.2                                                                              0                                             sec-C.sub.4 H.sub.9                                                                           (CH.sub.2).sub.2                                                                              0                                             n-C.sub.5 H.sub.11                                                                            (CH.sub.2).sub.2                                                                              0                                             i-C.sub.5 H.sub.11                                                                            (CH.sub.2).sub.2                                                                              0                                             sec-C.sub.5 H.sub.11                                                                          (CH.sub.2).sub.2                                                                              0                                             neo-C.sub.5 H.sub.11                                                                           (CH.sub.2).sub.2                                                                             0                                             n-C.sub.6 H.sub.13                                                                            (CH.sub.2).sub.2                                                                              0                                             i-C.sub.6 H.sub.13                                                                            (CH.sub.2).sub.2                                                                              0                                             sec-C.sub.6 H.sub.13                                                                          (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 CH(C.sub.2 H.sub.5).sub.2                                                            (CH.sub.2).sub.2                                                                              0                                              ##STR25##      (CH.sub.2).sub.2                                                                              0                                             CH.sub.3        CH(CH.sub.3)CH.sub.2                                                                          0                                             C.sub.2 H.sub.5 CH(CH.sub.3)CH.sub.2                                                                          0                                             n-C.sub.3 H.sub.7                                                                             CH(CH.sub.3)CH.sub.2                                                                          0                                             i-C.sub.3 H.sub.7                                                                             CH(CH.sub.3)CH.sub.2                                                                          0                                             n-C.sub.4 H.sub.9                                                                             CH(CH.sub.3)CH.sub.2                                                                          0                                             i-C.sub.4 H.sub.9                                                                             CH(CH.sub.3)CH.sub.2                                                                          0                                             sec-C.sub.4 H.sub.9                                                                           CH(CH.sub.3)CH.sub.2                                                                          0                                             n-C.sub.5 H.sub.11                                                                            CH(CH.sub.3)CH.sub.2                                                                          0                                             i-C.sub.5 H.sub.11                                                                            CH(CH.sub.3)CH.sub.2                                                                          0                                             sec-C.sub.5 H.sub.11                                                                          CH(CH.sub.3)CH.sub.2                                                                          0                                             neo-C.sub.5 H.sub.11                                                                          CH(CH.sub.3)CH.sub.2                                                                          0                                             CH.sub.3        C(CH.sub.3).sub.2 CH.sub.2                                                                    0                                             C.sub.2 H.sub.5 C(CH.sub.3).sub.2 CH.sub.2                                                                    0                                             n-C.sub.3 H.sub.7                                                                             C(CH.sub.3).sub.2 CH.sub.2                                                                    0                                             i-C.sub.3 H.sub.7                                                                             C(CH.sub.3).sub.2 CH.sub.2                                                                    0                                             sec-C.sub.4 H.sub.9                                                                           C(CH.sub.3).sub.2 CH.sub.2                                                                    0                                             C.sub.2 H.sub.5 CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             n-C.sub.3 H.sub.7                                                                             CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             i-C.sub.3 H.sub.7                                                                             CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             sec-C.sub.4 H.sub.11                                                                          CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             CH.sub.3        (CH.sub.2).sub.2                                                                              1                                             C.sub.2 H.sub.5 (CH.sub.2).sub.2                                                                              1                                             n-C.sub.3 H.sub.7                                                                             (CH.sub.2).sub.2                                                                              1                                             i-C.sub.3 H.sub.7                                                                             (CH.sub.2).sub.2                                                                              1                                             n-C.sub.4 H.sub.9                                                                             (CH.sub.2).sub.2                                                                              1                                             i-C.sub.4 H.sub.9                                                                             (CH.sub.2).sub.2                                                                              1                                             sec-C.sub.4 H.sub.9                                                                           (CH.sub.2).sub.2                                                                              1                                             C.sub.2 H.sub.5 CH.sub.2 CH(CH.sub.3)                                                                         1                                             n-C.sub.3 H.sub.7                                                                             CH.sub.2 CH(CH.sub.3)                                                                         1                                             i-C.sub.3 H.sub.7                                                                             CH.sub.2 CH(CH.sub.3)                                                                         1                                             sec-C.sub.3 H.sub.7                                                                           CH.sub.2 CH(CH.sub.3)                                                                         1                                             i-C.sub.3 H.sub.7                                                                             CH.sub.2 C(CH.sub.3).sub.2                                                                    1                                             i-C.sub.3 H.sub.7                                                                             CH(CH.sub.3)CH(CH.sub.3)                                                                      1                                             C.sub.2 H.sub.5 OCH.sub.2       0                                             n-C.sub.3 H.sub.7                                                                             OCH.sub.2       0                                             i-C.sub.3 H.sub.7                                                                             OCH.sub.2       0                                             n-C.sub.4 H.sub.9                                                                             OCH.sub.2       0                                             i-C.sub.4 H.sub.9                                                                             OCH.sub.2       0                                             sec-C.sub.4 H.sub.9                                                                           OCH.sub.2       0                                             CH.sub.2 CHCH.sub.2                                                                           (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 CHCH.sub.2                                                                           CH(CH.sub.3)CH.sub.2                                                                          0                                             CH.sub.2 CHCH.sub.2                                                                           CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             CH.sub.2 CHCH.sub.2                                                                           C(CH.sub.3).sub.2 CH.sub.2                                                                    0                                             CH.sub.2 CHCH.sub.2                                                                           (CH.sub.2).sub.2                                                                              1                                             CH.sub.2 CHCH.sub.2                                                                           CH(CH.sub.3)CH.sub.2                                                                          1                                             CH.sub.2 CHCH.sub.2                                                                           CH(CH.sub.3 )CH(CH.sub.3)                                                                     1                                              ##STR26##      (CH.sub.2).sub.2                                                                              0                                              ##STR27##      CH(CH.sub.3)CH.sub.2                                                                          0                                              ##STR28##      CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                              ##STR29##      CH.sub.2 C(CH.sub.3).sub.2                                                                    0                                              ##STR30##      (CH.sub.2).sub.2                                                                              1                                              ##STR31##      (CH.sub.2).sub.2                                                                              0                                              ##STR32##      CH(CH.sub.3)CH.sub.2                                                                          0                                              ##STR33##      C(CH.sub.3).sub.2 CH.sub.2                                                                    0                                              ##STR34##      (CH.sub.2).sub.2                                                                              1                                             CH.sub.2 CHCHCH.sub.3                                                                         (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 CHCHCH.sub.3                                                                         CH(CH.sub.3)CH.sub. 2                                                                         0                                             CH.sub.2 CHCHCH.sub.3                                                                         (CH.sub.2).sub.2                                                                              1                                             CH.sub.2 CCH    (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 CCH    CH(CH.sub.3)CH.sub.2                                                                          0                                             CH.sub.2 CCH    CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             CH.sub.2 CCH    CH.sub.2 C(CH.sub.3).sub.2                                                                    0                                             CH.sub.2 CCH    (CH.sub.2).sub.2                                                                              1                                             CH.sub.2 CCH    (CH.sub.2).sub.2                                                                              2                                             CH.sub.2 CCH    CH(CH.sub.3)CH(CH.sub.2)                                                                      1                                             CH.sub.2 CCH    CH(CH.sub.3)CH.sub.2                                                                          1                                             CH.sub.2 C CH   CH.sub.2 C(CH.sub.3).sub.2                                                                    1                                              ##STR35##      (CH.sub.2).sub.2                                                                              0                                              ##STR36##      CH(CH.sub.3)CH.sub.2                                                                          0                                              ##STR37##      CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                              ##STR38##      CH.sub.2 C(CH.sub.3).sub.2                                                                    0                                              ##STR39##      (CH.sub.2).sub.2                                                                              1                                              ##STR40##      CH(CH.sub.3)CH.sub.2                                                                          1                                             CH.sub.2 CCCH.sub.3                                                                           (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 C CCH.sub.3                                                                          CH.sub.2 CH(CH.sub.3)                                                                         0                                             CH.sub.2 CCCH.sub.3                                                                           CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             CH.sub.2 CCCH.sub.3                                                                           (CH.sub.2).sub.2                                                                              1                                             CH.sub.2 CH CH.sub.2                                                                          OCH.sub.2       0                                              ##STR41##      OCH.sub.2       0                                              ##STR42##      OCH.sub.2       0                                              ##STR43##      OCH.sub.2       0                                             CH.sub.2 CCH    OCH.sub.2       0                                              ##STR44##      OCH.sub.2       0                                             CH.sub.2 CCCH.sub.3                                                                           OCH.sub.2       0                                             CH.sub.2 OCH.sub.3                                                                            CH.sub.2        0                                             CH.sub.2 OC.sub.2 H.sub.5                                                                     CH.sub.2        0                                             CH.sub.2 O(n)C.sub.3 H.sub.7                                                                  CH.sub.2        0                                             CH.sub.2 O(n)C.sub.4 H.sub.9                                                                  CH.sub.2        0                                             CH.sub.2 OCH.sub.3                                                                            (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 OC.sub.2 H.sub.5                                                                     (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 O(n)C.sub.3 H.sub.7                                                                  (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 O(n)C.sub.4 H.sub.9                                                                  (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 CH.sub.2 OCH.sub.3                                                                   (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 CH.sub.2 OC.sub.2 H.sub.5                                                            (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 OCH.sub.3                                                                            OCH.sub.2       0                                             CH.sub.2 OC.sub.2 H.sub.5                                                                     OCH.sub.2       0                                             CH.sub.2 OCH.sub.3                                                                            CH.sub.2 CH(CH.sub.3)                                                                         0                                             CH.sub.2 OCH.sub.3                                                                            CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             i-C.sub.3 H.sub.7                                                                             (CH.sub.2).sub.3                                                                              0                                             CH.sub.2 CHCH.sub.2                                                                           (CH.sub.2).sub.3                                                                              0                                             CH.sub.2 CCH    (CH.sub.2).sub.3                                                                              0                                             CF.sub.3        CH(CH.sub.3)CH.sub.2                                                                          0                                             CF.sub.3        CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             CF.sub.2 H      CH.sub.2        0                                             CF.sub.2 H      CH(CH.sub.3)    0                                             CF.sub.2 H      C(CH.sub.3).sub.2                                                                             0                                             CF.sub.2 H      (CH.sub.2).sub.2                                                                              0                                             CF.sub.2 H      CH(CH.sub.3)CH.sub.2                                                                          0                                             CF.sub.2 H      CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             CF.sub.2 CF.sub.2 CH.sub.3                                                                    (CH.sub.2)      0                                             CF.sub.2 CF.sub.2 CH.sub.3                                                                    CH(CH.sub.3)    0                                             CF.sub.2 CF.sub.2 CH.sub.3                                                                    C(CH.sub.3).sub.2                                                                             0                                             CF.sub.2 CF.sub.2 CH.sub.3                                                                    (CH.sub.2).sub.2                                                                              0                                             CF.sub.2 CF.sub.2 CH.sub.3                                                                    CH(CH.sub.3)CH.sub.2                                                                          0                                             CF.sub.2 CF.sub.2 CH.sub.3                                                                    CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             CH.sub.2 SCH.sub.3                                                                            CH.sub.2        0                                             CH.sub.2 SCH.sub.3                                                                             CH(CH.sub.3)   0                                             CH.sub.2 SCH.sub.3                                                                            C(CH.sub.3).sub.2                                                                             0                                             CH.sub.2 SCH.sub.3                                                                            (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 SCH.sub.3                                                                            CH(CH.sub.3)CH.sub.2                                                                          0                                             CH.sub.2 SCH.sub.3                                                                            CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             CH.sub.2 SC.sub.2 H.sub.5                                                                     CH.sub.2        0                                             CH.sub.2 SC.sub.2 H.sub.5                                                                     CH(CH.sub.3)    0                                             CH.sub.2 SC.sub.2 H.sub.5                                                                     C(CH.sub.3).sub.2                                                                             0                                             CH.sub.2 SC.sub.2 H.sub.5                                                                     (CH.sub.2).sub.2                                                                              0                                             CH.sub.2 SC.sub.2 H.sub.5                                                                     CH(CH.sub.3)CH.sub.2                                                                          0                                             CH.sub.2 SC.sub.2 H.sub.5                                                                     CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             CH(CH.sub.3)SCH.sub.3                                                                         CH.sub.2        0                                             CH(CH.sub.3)SCH.sub.3                                                                         CH(CH.sub.3)    0                                             CH(CH.sub.3)SCH.sub.3                                                                         C(CH.sub.3).sub.2                                                                             0                                             CH(CH.sub.3)SCH.sub.3                                                                         (CH.sub.2).sub.2                                                                              0                                             CH(CH.sub.3)SCH.sub.3                                                                         CH(CH.sub.3)CH.sub.2                                                                          0                                             CH(CH.sub.3)SCH.sub.3                                                                         CH(CH.sub. 3)CH(CH.sub.3)                                                                     0                                             CH(CH.sub.3)SC.sub.2 H.sub.5                                                                  CH.sub.2        0                                             CH(CH.sub.3)SC.sub.2 H.sub.5                                                                  CH(CH.sub.3)    0                                             CH(CH.sub.3)SC.sub.2 H.sub.5                                                                  C(CH.sub.3).sub.2                                                                             0                                             CH(CH.sub.3)SC.sub.2 H.sub.5                                                                  (CH.sub.2).sub.2                                                                              0                                             CH(CH.sub.3)SC.sub.2 H.sub.5                                                                  CH(CH.sub.3)CH.sub.2                                                                          0                                             CH(CH.sub.3)SC.sub.2 H.sub.5                                                                  CH(CH.sub.3)CH(CH.sub.3)                                                                      0                                             ______________________________________                                    

Some typical embodiments of the invention for production of thebenzothiazolones (I) are illustratively shown in the following Examples.

EXAMPLE 1

To a dispersion of sodium hydride (60% oil; 31 mg) in dryN,N-dimethylformamide (3 ml) was added2-[6fluoro-2(3H)-benzothiazolon-5-yl]-4,5,6,7-tetrahydro-2H-benzotriazole-1-oxide(220 mg) at 0° C., and the resultant mixture was stirred at the sametemperature for 30 minutes, followed by addition of propargyl bromide(94 mg). The mixture was allowed to react at 50° to 60° C. for 3 hours.Water was added to the reaction mixture, which was then extracted withethyl acetate. The extract was washed with water, dried andconcentrated. The residue was purified by silica gel thin layerchromatography using a mixture of ethyl acetate and toluene (1:9) as aneluent to give2-[3-(2-propynyl)-6-fluoro-2(3H)-benzothiazolon-5-yl]-4,5,6,7-tetrahydro-2H-benzotriazole-1-oxide(Compound No. 5; 120 mg). n²⁵.4_(D) 1.5988.

EXAMPLE 2

6-Fluoro-3-(1-methylethyl)-2(3H)-benzothiazolon5-ylhydrazine (1.11 g)and 4-(3-hydroxyimino1-cyclohexen2-yl)morpholine (0.90 g) were dissolvedin ethanol (20 ml), a catalytic amount of acetic acid was added thereto,and the resultant mixture was heated under reflux for 3 hours. Water wasadded to the reaction mixture, which was then extracted with ethylacetate. The extract was distilled under reduced pressure to remove thesolvent and combined with a mixture of 15% aqueous pyridine (30 ml),tetrahydrofuran (20 ml) and cupric sulfate pentahydrate (2.2 g),followed by refluxing for 2 hours. After cooling, water and ethylacetate were added to the reaction mixture. The organic layer wasseparated from the water layer, washed with dilute hydrochloric acid,dried and concentrated. The residue was crystallized from ether to give2-[3-isopropyl6-fluoro-2(3H)-benzothiazolon-5-yl]-4,5,6,7-tetrahydro-2H-benzotriazole-1-oxide(Compound No. 3; 0.7 g). m.p., 92.5° C.

In the same manner as above, the benzothiazolones (I) as shown in Table2 were prepared.

                                      TABLE 2                                     __________________________________________________________________________     ##STR45##                   (I)                                               Com- pound No.                                                                     R                                                                                        ##STR46##      Physical property                             __________________________________________________________________________    1    C.sub.2 H.sub.5                                                                           ##STR47##     n.sub.D.sup.24.5 1.5940                        2    n-C.sub.3 H.sub.7                                                                         ##STR48##     m.p., 141-142° C.                       3    i-C.sub.3 H.sub.7                                                                         ##STR49##     m.p., 92.5° C.                          4    CH.sub.2 CHCH.sub.2                                                                       ##STR50##     n.sub.D.sup.24.5 1.5964                        5    CH.sub.2 CCH                                                                              ##STR51##     n.sub.D.sup.25.4 1.5988                        6    CH.sub.2 OCH.sub.3                                                                        ##STR52##     m.p., 139-140° C.                       7    i-C.sub.3 H.sub.7                                                                         ##STR53##     glassy                                         8    i-C.sub.3 H.sub.7                                                                         ##STR54##     glassy                                         9    i-C.sub.3 H.sub.7                                                                         ##STR55##     glassy                                         10   i-C.sub.3 H.sub.7                                                                         ##STR56##     glassy                                         11   i-C.sub.3 H.sub.7                                                                         ##STR57##     m.p., 145-146° C.                       12   i-C.sub.3 H.sub.7                                                                         ##STR58##     glassy                                         13   i-C.sub.3 H.sub.7                                                                         ##STR59##     m.p., 185.7° C.                         14   CH.sub.2 CH.sub.2 F                                                                       ##STR60##     resinous                                       15   CH(CH.sub.3)OCH.sub.3                                                                     ##STR61##     m.p., 175-175.5° C.                     16   CH(CH.sub.3)OC.sub.2 H.sub.5                                                              ##STR62##     m.p., 168.5-169° C.                     17   CH.sub.2 SCH.sub.3                                                                        ##STR63##     m.p., 179-180° C.                       __________________________________________________________________________

The starting compounds (II) and (IV) in the process of this inventionmay be produced according to the following scheme: ##STR64## where R, Xand n are each as defined above.

Each reaction as set forth above will be hereinafter explained indetail.

(1) Production of the compound (II) from the compound (VI):

In the same manner as in the conversion of the compound (IV) to thebenzothiazolone (I), 6-fluoro-2(3H)-benzothiazolon-5-ylhydrazine (VI) isreacted with 1 to 1.05 equivalents of the compound (V) in a solvent suchas alcohols (e.g. methanol, ethanol, cellosolve) or ethers (e.g.1,4-dioxane, tetrahydrofuran) in the presence of a small amount of anacid (e.g. acetic acid, p-toluenesulfonic acid) and then reacting theresultant product with 1 to 1.5 equivalents of an oxidizing agent (e.g.cupric sulfate, platinum oxide, zinc tetraacetate) in 1 equivalent tolarge excess of a tertiary amine (e.g. pyridine) and a solvent such aswater, alcohols (e.g. methanol, ethanol) or ethers (e.g. 1,4-dioxane,tetrahydrofuran, diethyl ether, diisopropyl ether, diethylene glycoldimethyl ether) at a temperature of 10° to 100° C. for a period of 1 to10 hours.

After completion of the reaction, the reaction mixture may bepost-treated by a per se conventional procedure such as dilution withwater, extraction with an organic solvent and concentration. If desired,the reaction product may be further purified by means of chromatographyor recrystallization.

A typical example for production of the compound (II) is illustrativelyshown in the following Example.

EXAMPLE 3

6-Fluoro-2(3H)-benzothiazolon-5-ylhydrazine (6.60 g) and4-(2-hydroxyimino-1(6)-cyclohexen-1-yl)morpholine (6.50 g) weredissolved in ethanol (120 ml), a catalytic amount of acetic acid wasadded thereto, and the resulting mixture was heated under reflux for 5hours. Water was added thereto, and the reaction mixture was extractedwith ethyl acetate. The extract was concentrated, a mixture of cupricsulfate pentahydrate (16.0 g), water (64 g), 15% aqueous pyridine (160g) and tetrahydrofuran (128 ml) was added thereto, and the resultingmixture was refluxed for 5 hours. After cooling, water and ethyl acetatewere added thereto. The organic layer was separated from the aqueouslayer, washed with dilute hydrochloric acid, dried and concentrated. Theresidue was purified by silica gel column chromatography using a mixtureof ethyl acetate and hexane (1:9) as an eluent to give2-[6-fluoro-2(3H)-benzothiazolon-5-yl]-4,5,6,7-tetrahydro-2H-benzotriazole-1-oxide(0.62 g).

¹ H-NMR (δ, CDCl₃ +DMSO-d₆): 1.5-2.2 (br, 4H), 2.3-2.9 (br, 4H), 7.21(d, 1H, J=6 Hz), 7.46 (d, 1H, J=9 Hz).

(2) Production of the compound (VI) from the compound (VII) andproduction of the compound (IV) from the compound (VIII):

The compounds (IV) and (VI) are obtainable according to the method asdescribed in J.Chem.Soc., (c), 1970, 2106. Namely, the compound (IV) or(VI) may be prepared by treating the compound (VIII) or (VII) with analkali metal nitrite (e.g. sodium nitrite, potassium nitrite) in thepresence of a mineral acid (e.g. sulfuric acid, hydrochloric acid) at atemperature of about -5° to 5° C. for a period of about 0.5 to 24 hours,followed by treatment of the resultant diazo compound with a reducingagent (e.g. stannous chloride, zinc, sodium sulfite) at a temperature ofabout -20° to 50° C. for a period of about 1 to 24 hours. In thereaction, each of the alkali metal nitrite and the reducing agent may beused in an amount of about 1 to 2 equivalents to the compound (VIII) or(VII).

When crystals were precipitated in the reaction mixture, they arecollected by filtration, dissolved in water, neutralized with an alkaliand extracted with an organic solvent. When not precipitated, thereaction mixture is neutralized with an alkali and extracted with anorganic solvent. The extract is washed with water, dried andconcentrated, if necessary, followed by purification such aschromatography.

A typical example for production of the compound (IV) or the compound(VI) is illustratively shown in the following Example.

EXAMPLE 4

A suspension of 5-amino-6-fluoro-2(3H)-benzothiazolone (12.98 g) inconc. hydrochloric acid (70 g) was cooled to 0° to 5° C., and asaturated aqueous solution of sodium nitrite (5.08 g) was dropwise addedthereto at 0° to 5° C., followed by stirring at the same temperature for30 minutes. The resultant mixture was cooled to -20° C., and a solutionof stannous chloride (28.06 g) in conc. hydrochloric acid (30 g) wasadded thereto all at once, followed by stirring at 0° C. for 2 hours.The reaction mixture was neutralized with potassium hydroxide, acolloidal substance originated from stannous chloride was removed bycelite and the resultant solution was extracted with ethyl acetate. Theextract was washed with water, dried over magnesium sulfate andconcentrated to give 6-fluoro-2(3H)-benzothiazolon-5-ylhydrazine (6.60g).

¹ H-NMR (δ, CDCl₃ +DMSO-d₆) 3.5-4.5 (br, 2H), 5.7-6.3 (br, 1H), 6.97 (d,1H, J=9 Hz), 7.00 (d, 1H, J=6 Hz).

In the same manner as above, the compounds (IV) and (VI) as shown inTable 3 were obtained.

                  TABLE 3                                                         ______________________________________                                         ##STR65##                 (IV or VI)                                         R           Physical property                                                 ______________________________________                                        H           .sup.1 H-NMR (δ, CDCl.sub.3 + DMSO-d.sub.6): 3.5-4.5                    (br, 2H), 5.7-6.3 (br, 1H), 6.97 (d, 1H,                                      J = 9Hz), 7.00 (d, 1H, J = 6Hz)                                   i-C.sub.3 H.sub.7                                                                         m.p., 66° C.                                               CH.sub.2 CHCH.sub.2                                                                       m.p., 129.7° C.                                            CH.sub.2 CCH                                                                              m.p., 181.8° C.                                            ______________________________________                                    

For the practical use of the benzothiazolones (I), they are usuallyformulated with conventional solid or liquid carriers or diluents aswell as surface active agents or auxiliary agents into conventionalpreparation forms such as emulsifiable concentrates, wettable powders,suspensions and granules. The content of the benzothiazolone (I) as theactive ingredient in such preparation forms is usually within a range ofabout 0.05 to 90% by weight, preferably of about 0.1 to 80% by weight.Examples of the solid carrier or diluent are fine powders or granules ofkaolin clay, attapulgite clay, bentonite, terra alba, pyrophyllite,talc, diatomaceous earth, calcite, walnut powders, urea, ammoniumsulfate and synthetic hydrous silicate, etc. As the liquid carrier ordiluent, there may be exemplified aromatic hydrocarbons (e.g. xylene,methylnaphthalene), alcohols (e.g. isopropanol, ethylene glycol,cellosolve), ketones (e.g. acetone, cyclohexanone, isophorone), soybeanoil, cotton seed oil, dimethylsulfoxide, N,N-dimethylformamide,acetonitrile, water, etc.

The surface active agent used for emulsification, dispersion orspreading may be of any type, for instance, either anionic or non-ionic.Examples of the surface active agent include alkylsulfates,alkylarylsulfonates, dialkylsulfosuccinates, phosphates ofpolyoxyethylenealkylaryl ethers, polyoxyethylene alkyl ethers,polyoxyethylene alkylaryl ethers, polyoxyethylene polyoxypropylene blockcopolymer, sorbitan fatty acid esters, polyoxyethylene sorbitan fattyacid esters, etc. Examples of the auxiliary agents includeligninsulfonates, sodium alginate, polyvinyl alcohol, gum arabic, CMC(carboxymethyl cellulose), PAP (isopropyl acid phosphate), etc.

Practical embodiments of the herbicidal composition according to thepresent invention are illustratively shown in the following exampleswherein parts are by weight. The compound number of the activeingredient corresponds to the one in Table 2.

FORMULATION EXAMPLE 1

Fifty parts of Compound No. 2 or 11, 3 parts of calcium ligninsulfonate,2 parts of sodium laurylsulfate and 45 parts of synthetic hydroussilicate are mixed well while being powdered to obtain a wettablepowder.

FORMULATION EXAMPLE 2

Ten parts of Compound No. 3 or 4, 14 parts ofpolyoxyethylenestyrylphenyl ether, 6 parts of calciumdodecylbenzenesulfonate, 25 parts of xylene and 45 parts ofcyclohexanone are mixed well to obtain an emulsifiable concentrate.

FORMULATION EXAMPLE 3

Two parts of Compound No. 6 or 8, 1 part of synthetic hydrous silicate,2 parts of calcium ligninsulfonate, 30 parts of bentonite and 65 partsof kaolin clay are mixed well while being powdered. The mixture is thenkneaded with water, granulated and dried to obtain granules.

FORMULATION EXAMPLE 4

Twenty-five parts of Compound No. 7 or 9 is mixed with 3 parts ofpolyoxyethylene sorbitan monooleate, 3 parts of carboxymethyl celluloseand 69 parts of water and pulverized until the particle size of themixture becomes less than 5 microns to obtain a suspension.

FORMULATION EXAMPLE 5

Five parts of Compound No. 5, 9 or 13, 14 parts ofpolyoxyethylenestyrylphenyl ether, 6 parts of calciumdodecylbenzenesulfonate, 30 parts of xylene and 45 parts ofN,N-dimethylformamide are mixed well to obtain an emulsifiableconcentrate.

The benzothiazolones (I) thus formulated in any suitable preparationform are useful for pre-emergence or post-emergence control of undesiredweeds by soil or foliar treatment as well as flood fallowing treatment.These treatments include the application to the soil surface prior to orafter the transplanting or the incorporation into the soil. The foliartreatment may be effected by spraying the herbicidal compositioncontaining the benzothiazolones (I) over the top of the plants. It mayalso be applied directly to the weeds if care is taken to keep thechemical off the crop foliage.

The benzothiazolones (I) of the present invention may be used togetherwith other herbicides to improve their activity as herbicides, and insome cases, a synergistic effect can be expected. Further, they may beapplied in combination with insecticides, acaricides, nematocides,fungicides, plant growth regulators, fertilizers, soil improvers, etc.

Furthermore, the benzothiazolones (I) can be used as herbicidesapplicable to agricultural plowed fields as well as paddy fields. Theyare also useful as herbicides to be employed for orchards, pasture land,lawns, forests, nonagricultural fields, etc.

The dosage rate of the benzothiazolones (I) may vary depending on theprevailing weather conditions, the formulation used, the prevailingseason, the mode of application, the soil involved, the crop and weedspecies, etc. Generally, however, the dosage rate is from 0.02 to 100grams, preferably from 0.05 to 50 grams, of the active ingredient perare. The herbicidal composition of the invention formulated in the formof an emulsifiable concentrate, a wettable powder or a suspension mayordinarily be employed by diluting it with water at a volume of about 1to 10 liters per are, if necessary, with addition of an auxiliary agentsuch as a spreading agent. Examples of the spreading agent include, inaddition to the surface active agents as noted above, polyoxyethyleneresin acid (ester), ligninsulfonate, abietylenic acid salt,dinaphthylmethanedisulfonate, paraffin, etc. The composition formulatedin the form of granules may be normally applied as such withoutdilution.

The biological data of the benzothiazolones (I) as herbicides will beillustratively shown in the following Examples wherein the phytotoxicityto crop plants and the herbicidal activity on weeds were observedvisually as to the degree of germination as well as the growthinhibition and rated with an index 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10,in which the numeral "0" indicates no material difference as seen incomparison with the untreated plant and the numeral "10" indicates thecomplete inhibition or death of the test plants.

The following compound was used for comparison.

    ______________________________________                                        Compound                                                                      No.       Chemical structure                                                                             Remarks                                            ______________________________________                                                   ##STR66##       Commercially available herbi- cide                 ______________________________________                                                                   "benazolin"                                    

TEST EXAMPLE 1

Cylindrical plastic pots (diameter, 10 cm; height, 10 cm) were filledwith upland field soil, and the seeds of Japanese millet, tallmorningglory and velvetleaf were sowed therein and covered with soil. Adesignated amount of the test compound formulated in an emulsifiableconcentrate as in Formulation Example 2 was diluted with water, and thedilution was sprayed onto the soil surface by means of a small handsprayer at a spray volume of 10 liters per are. The test plants werefurther grown in a greenhouse for 20 days, and the herbicidal activitywas examined. The results are shown in Table 4.

                  TABLE 4                                                         ______________________________________                                                    Herbicidal activity                                               Compound Dosage   Japanese  Tall morning-                                                                          Velvet-                                  No.      (g/are)  millet    glory    leaf                                     ______________________________________                                        1        20       10        10       10                                       2        20       10        10       10                                       3        20       10        10       10                                       4        20       10        10       10                                       5        20       10        10       10                                       6        20       10        10       10                                       7        20       10        10       10                                       8        20       10        10       10                                       9        20       10        10       10                                       10       20       10        10       10                                       11       20       10        10       10                                       12       20       10        10       10                                       13       20       10        10       10                                       14       20       10        10       10                                       15       20       10        10       10                                       16       20       10        10       10                                       17       20       10        10       10                                       ______________________________________                                    

TEST EXAMPLE 2

Cylindrical plastic pots (diameter, 10 cm; height, 10 cm) were filledwith upland field soil, and the seeds of Japanese millet, radish andvelvetleaf were sowed therein and cultivated in a greenhouse for 10days. A designated amount of the test compound formulated in anemulsifiable concentrate as in Formulation Example 2 was diluted withwater containing a spreading agent, and the dilution was sprayed overthe foliage of the test plants by means of a small hand sprayer at aspray volume of 10 liters per are. The test plants were further grown inthe greenhouse for 20 days, and the herbicidal activity was examined.The results are shown in Table 5.

                  TABLE 5                                                         ______________________________________                                        Compound                                                                              Dosage   Herbicidal activity                                          No.     (g/are)  Japanese millet                                                                           Radish  Velvetleaf                               ______________________________________                                        1       20       10          10      10                                       2       20       10          10      10                                       3       20       10          10      10                                       4       20       10          10      10                                       5       20       10          10      10                                       6       20       10          10      10                                       7       20       10          10      10                                       8       20       10          10      10                                       9       20       10          10      10                                       10      20       10          10      10                                       11      20       10          10      10                                       12      20       10          10      10                                       13      20       10          10      10                                       14      20       10          10      10                                       15      20       10          10      10                                       16      20       10          10      10                                       17      20       10          10      10                                       ______________________________________                                    

TEST EXAMPLE 3

Cylindrical plastic pots (diameter, 8 cm,; height, 12 cm) were filledwith paddy field soil, and the seeds of barnyardgrass (Echinochloaoryzicola), broad-leaved weeds (i.e. common falsepimpernel, indiantoothcup, waterwort) were sowed in 1 to 2 cm depth. Water was pouredtherein to make a flooded condition, and tubers of arrowhead weretransplanted therein, and the test plants were grown in a greenhouse.Six days (at that time weeds began to germinate) thereafter, adesignated amount of the test compound formulated in an emulsifiableconcentrate as in Formulation Example 2 or 5 and diluted with water (5ml) was applied to the pots by perfusion. The test plants were grown foran additional 20 days in the greenhouse, and the herbicidal activity wasexamined. The results are shown in Table 6.

                  TABLE 6                                                         ______________________________________                                                   Herbicidal activity                                                Compound Dosage  Barnyard-   Broad-leaved                                                                           Arrow-                                  No.      (g/are) grass       weed     head                                    ______________________________________                                        3        0.63    9           10       10                                      4        0.63    9           10       10                                      5        0.63    10          10       10                                      8        0.63    10          10       10                                      9        0.63    10          10       10                                      11       0.63    10          10       10                                      13       0.63    9           10       10                                      A        0.63    0            1        0                                      ______________________________________                                    

TEST EXAMPLE 4

Vats (33 cm×23 cm×11 cm) were filled with upland field soil, and theseeds of cotton, common cocklebur, black nightshade, barnyardgrass(Echinochloa crus-galli) and johnsongrass were sowed therein to 1 to 2cm depth. A designated amount of the test compound formulated in anemulsifiable concentrate as in Formulation Example 2 or 5 was dilutedwith water, and the dilution was sprayed onto the soil surface by meansof a small hand sprayer at a spray volume of 10 liters per are. The testplants were further grown outdoors for 20 days, and the herbicidalactivity was examined. The results are shown in Table 7.

                  TABLE 7                                                         ______________________________________                                                Herbicidal activity                                                   Com-                   Common Black Barn-                                     pound Dosage           cock-  night-                                                                              yard- Johnson-                            No.   (g/are) Cotton   lebur  shade grass grass                               ______________________________________                                        1     1.25    0        10     10    10    10                                  2     1.25    1        10     10     9    10                                  6     1.25    0        10     10    10    10                                  A     1.25    0         0      0     0     0                                  ______________________________________                                    

TEST EXAMPLE 4

Vats (33 cm×23 cm×11 cm) were filled with upland field soil, and theseeds of rice plant, velvetleaf, black nightshade, barnyardgrass(Echinochloa crus-galli) and green foxtail were sowed therein to 1 to 2cm depth. A designated amount of the test compound formulated in anemulsifiable concentrate as in Formulation Example 2 or 5 was dilutedwith water, and the dilution was sprayed onto the soil surface by meansof a small hand sprayer at a spray volume of 10 liters per are. The testplants were further grown in a greenhouse for 20 days, and theherbicidal activity was examined. The results are shown in Table 8.

                  TABLE 8                                                         ______________________________________                                                   Herbicidal activity                                                                               Black Barn-                                    Compound Dosage  Rice   Velvet-                                                                              night-                                                                              yard- Green                              No.      (g/are) plant  leaf   shade grass foxtail                            ______________________________________                                        7        2.5     1      10     9     --    8                                  8        2.5     1      10     9     7     7                                  9        2.5     1      10     10    8     10                                 10       2.5     0      10     --    --    10                                 A        2.5     0       0     0     0     0                                  ______________________________________                                    

TEST EXAMPLE 6

Vats (33 cm×23 cm×11 cm) were filled with upland field soil, and theseeds of wheat, catchweed bedstraw, common chickweed, persian speedwelland field pansy were sowed therein and cultivated for 18 days in agreenhouse. A designated amount of the test compound formulated in anemulsifiable concentrate as in Formulation Example 2 or 5 was dilutedwith water containing a spreading agent, and the dilution was sprayedover the foliage of the test plants by means of a small hand sprayer ata spray volume of 5 liters per are. The test plants were further grownin the greenhouse for 20 days, and the herbicidal activity was examined.At the time of the application, the test plants were generally at the 1to 4 leaf stage and in 2 to 12 cm height, although the growing stage ofthe test plants varied depending on their species. The results are shownin Table 9.

                  TABLE 9                                                         ______________________________________                                                 Herbicidal activity                                                  Com-                   Catch- Common Persian                                  pound Dosage           weed   chick- speed-                                                                              Field                              No.   (g/are)  Wheat   bedstraw                                                                             weed   well  pansy                              ______________________________________                                        2     0.1      3       10     9      10    10                                 3     0.1      3       9      --     10    10                                 4     0.1      1       9      --     10    10                                 6     0.1      3       10     0      10    10                                 A     0.1      0       0      0       0     0                                 ______________________________________                                    

TEST EXAMPLE 7

Vats (33 cm×23 cm×11 cm) were filled with upland field soil, and theseeds of barnyardgrass (Echinochloa crus-galli), johnsongrass, greenfoxtail, common cocklebur, tall morningglory, velvetleaf, blacknightshade and sicklepod were sowed therein and cultivated for 18 daysin a greenhouse. A designated amount of the test compound formulated inan emulsifiable concentrate as in Formulation Example 2 or 5 was dilutedwith water containing a spreading agent, and the dilution was sprayedover the foliage of the test plants by means of a small hand sprayer ata spray volume of 5 liters per are. The test plants were further grownin the greenhouse for 20 days, and the herbicidal activity was examined.At the time of the application, the test plants were generally at the 1to 4 leaf stage and in 2 to 12 cm height, although the growing stage ofthe test plants varied depending on their species. The results are shownin Table 10.

                                      TABLE 10                                    __________________________________________________________________________            Herbicidal activity                                                   Com-        Barn-    Common                                                                             Tall      Black                                     pound                                                                             Dosage                                                                            Green                                                                             yard-                                                                             Johnson-                                                                           cock-                                                                              morning-                                                                           Velvet-                                                                            night-                                                                            Sickle-                               No. (g/are)                                                                           foxtail                                                                           grass                                                                             grass                                                                              lebur                                                                              glory                                                                              leaf shade                                                                             pod                                   __________________________________________________________________________    1   0.2 10  8   9    10   10   10   10   9                                    3   0.2 8   7   10   10   10   10   10  10                                    5   0.2 10  10  10   10   10   10   10  10                                    7   0.2 8   --  --   --   10   10   10  10                                    10  0.2 10  --  8    --   10   10   10  10                                    13  0.2 0   8   8    10   10   10   10  10                                    A   0.2 0   0   0     0    0    0    0   0                                    __________________________________________________________________________

The invention being thus described, it will be obvious that the same waymay be varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are intendedto be included within the scope of the following claims.

What is claimed is:
 1. A compound of the formula: ##STR67## wherein X isa C₁ -C₄ alkylene group which may be substituted with at least onemethyl or a --OCH₂ -- group and n is an integer of 0, 1 or 2.